The present invention relates to submunition, especially for use during ground-level flight, transportable by a carrier to a target area and launchable there. The submunition covers a given path at a constant low altitude with controlled roll, said path lying at an angle to the flight axis of the carrier, said submunition having a target sensor and a payload.
Current possibilities for combatting groups of armored vehicles, especially tanks, at long range, are unsatisfactory. Thus, for deliberately combatting each individual target, in other words each tank, it is necessary to resort either to guided missiles, bombs, or guns, said methods requiring a considerable amount of mission time; or the area in which the vehicle group is located must be bombarded with statistically effective munitions, requiring a high weapon weight. Both types of attack also result in serious commitment and risk to the weapons carriers involved.
To overcome these disadvantages, target-seeking munitions and/or submunitions have already been developed. A type of submunition provided with a target-seeking fuse, during braked steep descent, scans the ground for target criteria in a narrowing spiral strip. When a target is detected, either a projectile-forming charge is fired at the target (target-seeking fuse submunition) or the submunition itself is steared to the target. In this solution, the submunition must be lifted to a high launching altitude, which in the case of air-to-ground weapons either means launching at this altitude and hence a considerable risk to the carrier, or in the case of launching at ground level, results in a high cost for elevating the submunition plus corresponding width distribution.
Another possibility consists in designing the submunition as a guided missile with a forward-looking target-seeking head. In this case, although the submunition heads for the target automatically after acquiring it, this type of guided missile design is very cumbersome and hence very expensive.
Hence, both solutions require long target acquisition distances as well as high sensitivity to other factors besides the targets to be attacked, giving these targets the opportunity to take countermeasures; the risk of attacking multiple targets cannot be ruled out either.
German Patent No. 3,345,601 teaches a submunition body which can be fired by an artillery weapon and can be launched by the latter over a target area while executing a turn; the submunition body is equipped with a target-acquisition sensor and a warhead in a hollow cylinder. Thus, with this known submunition body, there is no need for design-intensive measures that take up room and are functionally critical, to nullify kinetic energy following launching and parachute-braked descent into the target area, using the gyroscopic movement of a body designed as a thick disk, for example a flat cylinder, launched from the carrier projectile, to scan the target area using a target acquisition sensing spot. An arrangement of this kind is unsuitable for launching at high airspeeds, since it is only at very high natural rotational speeds that the body can be sufficiently stable, but this cannot as yet be controlled technologically for scanning and target accuracy. On the other hand, the target area that can be scanned, for example the area covered by spiral movement during ground-level flight, is very limited, and also because the unavoidable wobbling motion permits only a very short free-flight distance.
Effective attack against tank groups is only possible by launching this submunition from a high altitude, i.e. taking defensive measures into account.
The goal of the present invention is to provide submunition for attacking hardened mobile group targets, said submunition being launchable during ground-level flight and highly effective against modern tanks, ensuring independent target acquisition over large search areas and offering a low risk of multiple target attack at moderate cost.
Beginning with a submunition of the type described in greater detail above, it is proposed to achieve this goal by providing the submunition with an altimeter as well as a circuit to evaluate the altimeter readings, and with at least one airfoil controllable by this circuit and serving to control altitude and roll.
The submunition is launched from a carrier in flight and, guided by the altimeter, follows a low-altitude flight path parallel to the terrain. For high-speed ground-level applications, the submunition requires no drive because of its high kinetic energy, but may be equipped with one. During free flight at approximately constant low altitude, the submunition uses its target acquisition sensor to seek targets continuously in a strip beneath it. When a target is acquired, it directs an effect-oriented charge at the target and releases it.
The altimeter is advantageously a laser rangefinder which can simultaneously serve as the target contour acquisition sensor. To acquire the target, additional sensors can be used either as backups or as alternatives.
In a preferred embodiment, the submunition is equipped with a laser rangefinder for altitude and target measurement, and with a magnetic field sensor as a second target sensor, said rangefinder and sensor being connected to the payload ignition triggering circuit.
In this preferred embodiment, the laser sensor and payload are installed rigidly, axially parallel and at right angles to the direction of flight. To scan the search strip and measure the altitude, the submunition continuously performs an oscillating rolling motion.
In a second preferred embodiment, the target acquisition sensor and payload have certain width effects tuned to one another, i.e., they are offset with respect to the submunition's longitudinal axis. Once again, both are rigidly installed, axially parallel, and at right angles to the flight direction. In this case, the submunition flies without any rolling motion as it seeks the target.
The submunition according to the invention, especially suitable for use in high-speed ground-level flight, offers a favorable compromise between weapon cost and required transportation expense. Because of the short distance to the target (on the order of 20 to 50 m), the requirements for sensory devices, signal processing, and tolerances can be kept low. The short distance to the target also offers favorable target acquisition opportunities, since only minor target concealment by environmental factors can be expected and sensitivity to weather and defensive measures is low.
The submunition according to the invention, because of its gliding flight, covers a relatively wide strip of land measuring a few thousand square meters. With a suitable launching sequence from the carrier, the overlap of the search strips of several submunition bodies can be minimized. This provides a high degree of efficiency as a function of weapon weight and total target area, in other words a high probability of acquisition of all individual targets and a low probability of a double attack on mobile targets.
As a result of the long range of the submunition, especially at high transverse launch velocities, broad target areas can be covered. This makes this weapon, in conjunction with an adjustable launch sequence, insensitive to the direction of attack and target geometry; in other words, it offers greater operational flexibility.
Suitably adapted software allows the submunition according to the invention to be used to attack other groups of mobile targets or vehicles that are only roughly recognized by their positions, such as rocket positions, helicopter bases, motorized armored companies, artillery positions, command posts, etc. The flight path can also be curved horizontally either by structural design or optionally by suitable roll control.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.